1. Field of the Invention
The present invention relates to power device packages and methods of manufacturing the same, and more particularly, to power device packages including a plurality of stacked power semiconductor chips, and methods of manufacturing such power device packages.
2. Description of the Related Art
Recent developments in power electronics including such power devices as servo drivers, inverters, silicon-controlled rectifiers (SCRs) and converters are leading to manufacturing light and small power devices with excellent performance characteristics. Related researches are being actively conducted into smart or intelligent power modules in which a variety of power semiconductor chips and low power semiconductor chips such as IC chips for controlling the power semiconductor chips, can be integrated into one package.
In the conventional art, a plurality of semiconductor chips are individually mounted in die attach regions of a substrate in order to manufacture a plurality of semiconductor chips into one package. However, since the footprint area of the conventional power device package is increased as the number of mounted semiconductor chips increases, a desired compact power device package cannot be obtained. In addition, as the volume of the conventional power device package is increased, its electrical and mechanical reliability may be readily deteriorated due to temperature cycles that are repeated in a range of high temperature, and the life span of the power device package may be shorted.
Therefore, a stacked power device package, in which stacked power semiconductor chips are mounted on a substrate, has recently been suggested to minimize the footprint area and volume of the power device package. However, the cost for manufacturing the stacked power device package is relatively high because the wiring process for electrical connection between the stacked power semiconductor chips is complicated and expensive. Also, since vertical type power semiconductor devices such as insulated-gate bipolar transistors (IGBTs), metal-oxide-semiconductor (MOS) transistors, power diodes, power regulators, etc. use a lower surface of semiconductor chips as a drain electrode or a ground electrode, it is difficult to stack the power device chips into a power device package.